1. Field of the Invention
The present invention relates to an endoscope including a communication mechanism that eliminates a difference between an air pressure in an endoscope inside space and an atmospheric pressure in an external space.
2. Description of the Related Art
Before and after use of a conventional endoscope, in particular, a surgical endoscope among medical endoscopes, simple cleaning is performed on the endoscope. Additionally, autoclave sterilization treatment for exposing the endoscope to high-temperature and high-pressure sterilization steam and various kinds of gas sterilization treatments are applied to the endoscope. As the conventional endoscope subjected to such sterilization/disinfecting treatment and the like, there is an endoscope including a pipe sleeve, which includes a check valve that irreversibly performs ventilation from an internal space to an external space, and a ventilation valve adjacent to the pipe sleeve.
In the conventional endoscope having such a form, when the autoclave sterilization treatment or the like is performed, an endoscope internal space changes to a negative pressure state. The negative pressure state means a state in which pressure in the internal space is smaller than an atmospheric pressure in the external space. In this way, in a state in which the internal space remains in the negative pressure state and a difference between the pressure in the internal space and the atmospheric pressure in the external space remains occurred, for example, flexible bending rubber, which covers a bending section of an insertion section is in a press-contact state with a plurality of bending pieces made of metal. When the bending section is bent in that state, it is likely that the bending rubber is damaged because the bending rubber is, for example, rolled in or bit by the bending pieces. An operation switch of an endoscope operation section is sometimes covered by a switch cover made of an elastic body such as rubber. In the case of such a configuration, it is likely that operability of the operation switch and the like is hindered if the internal space remains in the negative pressure. Therefore, in the conventional endoscope of this type, a ventilation valve or the like is provided as a component for, after the sterilization treatment or the like is applied, before use of the endoscope, returning the negative pressure in the internal space to pressure substantially the same as the atmospheric pressure in the external space.
In this case, as a configuration for releasing the negative pressure in the endoscope internal space after the sterilization treatment in order to prevent damage or the like of the endoscope, various ideas have been proposed or put to practical use by, for example, Japanese Patent Application Laid-Open Publication No. 2013-46701, Japanese Patent Application Laid-Open Publication No. 2009-89765, Japanese Patent No. 3947270, and the like.
Means disclosed by Japanese Patent Application Laid-Open Publication No. 2013-46701 is a configuration for, in a process for detaching a sterilization cap from a sterilization pipe sleeve including a check valve mechanism, the sterilization cap pushes in a ventilation valve provided in a vicinity of the sterilization pipe sleeve to thereby bring the endoscope internal space into an open state.
Means disclosed by Japanese Patent Application Laid-Open Publication No. 2009-89765 and Japanese Patent No. 3947270 is a configuration for rotating a sterilization cap to thereby forcibly push in a check valve body of a check valve mechanism resisting an urging spring of the check valve body to bring a check valve into an open state.
On the other hand, means disclosed by Japanese Patent Application Laid-Open Publication No. 2004-89232 is a mechanism that is, in a water leak test, mounted with a connector of a water leak tester to open, without causing a check valve body in a check valve mechanism to operate, a bypass path provided in a portion other than the check valve mechanism.